Gearing



F. M. DAVIS.

HEARING- APPLICATION FILED MAY 24. 192W Patented Jan. 25,1921.

ATTO

g at

"n o are a 3M. E5 WE'WAUKW, WISGQINSTN.

enemies.

.iilpeolfleatlon of Letters Patent. v Pate ted J 25 19% Application filed my 24, 1920. semi m. 383,801.

citizen of the United States, and resident of Milwaukee, county of Milwaukee, and State of Wisconsin, have invented'new and useful Improvements in Gearing, of which-the'following is a description, reference being had to the accompanying drawmgs, which are a part of this specification.

The invention relates to gearing. I

The ob 'ect of the invention is to provide a simple and effective means for taking up the back-lash on worm gearing and 1s particularly useful on machines where accurafic workisdone." The invention furtherconsists-in the several features hereinafter set forth and more particularlfy defined by claims at the conclusion hereo In the drawings: Fi e 1 is a viewof the device embodying the lnvention, parts belng shown in section; Fig. 2 is a section taken on the line 2-2 ofjFig. 1; Fig. 3 is a section taken on the line 3-3 of Fig. 1; Fig. 4 is a view of the cover for the gear case. In the drawings the numeral 4: designates a worm wheel mes with a drive worm 5 on a shaft 5 which is journaled in a casing 6 having a removable cover. 6' and carnes a bevel gear 7..

The bevel gear 7 meshes with a bevel gear 8 loosely mounted on a shaft 9 'carryinga take up worm 10 also meshing. with: the worm wheel 4. The shaft 5 is journaled 1n bearings 20 on the casing 6 and the shaft 9 in bearings 21 on said casing. 1

The shaft 9 is driven through the bevel gears 7 and 8, the gear 8 being drivingly connected to said shift by means of pins 11, a

spider 12 and a retainer 13 which connection permits of a relative. rotary ad ustment of the shaft 9 with respect to the shaft 5' so that the worm 10 may be secured in adjusted position to bear upon-the o posite side of the teeth of the worm wheel m that of the driving worm. This connection is effected by providing a plurality of holes let n the gear 8 and a lurality of notches-15 1n the spider so that t e spider with the shaft 9 may be rotated to the desired ad usted pos tion the op site side of the teeth of the wheel from that against which the worm engages and be held in this position bythe plns .11, the retainer 13 having lugs which Y ma be disposed over the ends of the pins an when so set the retainer is secured in posltion by a set screw 16. The pins 11 have grooved ends 17 to permitJof their ready removal.

With the construction above described the worm 5 in driving bears against one side of the teeth of -the worm wheel as the side 18 while the worm 10, having been adjusted so that it bears on the opposite side of the teeth of worm wheel asthe side 19, is driven by the worm 5 through the gears 7 and 8. Conseguently the play or back-lash usually present 1n the ordinary worm gear is entirely taken up and as the gears wear down the wear is taken care of by a further adjustment of the worm 10. I Other forms of adjustment than that shown may be used and the worm' "10 wh1le preferably engaging the wheel 4 could *engage asimilar worm wheel directly con-.

nected to or integral with the'firstxworm wheel to take up the backlash.

I desire it to be understood that this invention. is not limited to any specific form or arrangement ofparts except in so far as such limitations are specified in the claims.

What I claim as new and desire to secure.

by Letters Patent is:

1. The combination, with a. worm and worm wheel, of a take-up worm meshing with said wheel and positively driven by the firstnamed worm and bearing upon the opposite side of the teeth of the worm wheel from that of the driving worm, and means for adjusting said take-up worm to compensate for wear.

2. The combination, with a worm and,

worm wheel, of a second worm meshing with saidwheel to take up back-lash, a positive gearing connection between the worms, and

means for adjusting said second worm to compensate for wear.

3. The combination, with a worm an worm wheel, of a take-up worm operatively connected to said worm wheel to take up back-lash, means forpositively driving both worms, and means for adjusting the take-up -w0rm to compensate for wear. to bring the worm 10 into engagement with said Wheel to'take up back-lash, a positivedriving connection between the worms, and means permitting turning of said second Worm relative to the wheel to an operative position and maintaining it in this position.

5. The combination, with it Worm and worm wheel, of a second Worm meshing with said wheel to take up back-lash, a positive gearing connection between the worms, and means for permitting turning oisaid second worm relative to the wheel to ofperative po- 10 sition and maintaining it in this position.

In testimony whereof, I :ifiix my signature.

FRANK M. DAVIS. 

